Narrator: Listen to part of a lecture in an environmental science class. Professor: Today we’re going to discuss the concept of 'urban heat islands.' This phenomenon occurs when cities are significantly warmer than surrounding rural areas. The main cause is the replacement of natural land cover with materials like concrete and asphalt, which absorb and retain heat. Additionally, waste heat from vehicles and buildings adds to the effect. Interestingly, the temperature difference can be as much as 10 degrees Fahrenheit on clear, calm nights. One solution is increasing vegetation, such as planting trees and creating green roofs. Trees provide shade and release moisture through transpiration, which cools the air. Another approach is using reflective materials for pavements and rooftops to reduce heat absorption. Some cities have implemented these strategies and reported noticeable temperature drops. However, challenges remain, including cost and maintenance. Nevertheless, addressing urban heat islands is crucial for public health and energy consumption. Now, what are some questions you have?
❓ Question According to the professor, what is a primary cause of the urban heat island effect?
A. A. Increased use of public transportation
B. B. The replacement of natural ground cover with heat-absorbing materials
C. C. High levels of air pollution from factories
D. D. Lack of wind due to tall buildings
✅ Correct Answer
B. The replacement of natural ground cover with heat-absorbing materials
TOEFL Listening Tips
Skim the questions first to predict the content
Watch for signal words in lectures and conversations (however, actually, in fact)
For main idea questions, focus on the beginning; for detail questions, focus on examples and data
For attitude questions, pay attention to the speaker's tone and word choice
Take notes on keywords; don't try to write down every word